Sometimes I write these posts because I’ve found something interesting. Sometimes I write them because I’ve done something I want to share. And, sometimes I write them because I don’t want to forget how I did something.
This is the latter.
I was trying to set up the debian-backports repository and after I’d added it to the sources.list file I kept getting this:
GPG error: http://deb.debian.org buster-backports main:The following signatures couldn't be verified because the publickey is not available: NO_PUBKEY
and then a 16-character hex number. To fix it, I did the following:
sudo apt-key adv --recv-keys --keyserver keyserver.ubuntu.com [16-character hex number] [other 16-character hex number (if applicable)]
That seems to have done the trick. Source information from:
https://backports.debian.org/Instructions/
https://rolfje.wordpress.com/2017/06/09/installing-gpg-keys-for-debian-backports/
https://answers.launchpad.net/ubuntu/+source/apt/+question/118944